Can't get the straight dope on this. I have an iphone 4s with Sprint. Nobody on their tech support knows about it, even though they're the first carrier in the country to roll it out. There's a ##CMAS# you can call but it says invalid code. Documentation on their site is for generic smartphones, not iphone. Other comments said it's not available in software yet and will be patched later. Anyone have a straight answer on this?